Drum-in-hat disc brake assembly

ABSTRACT

A drum-in-hat (DIH) disc brake assembly has a disc service brake, a DIH parking and emergency brake, and a parking brake anchor. A backing plate, an axle flange, and a caliper bracket each have at least two mounting apertures formed therethrough. The parking brake anchor includes a bracket portion having a pair of studs extending axially outwardly therefrom. The studs are structured and configured to extend through the respective mounting apertures of the backing plate, the axle flange, and the caliper bracket for securing the caliper bracket, parking brake anchor, and the backing plate to the axle flange.

BACKGROUND

Various embodiments of vehicle drum and disc brake assemblies aredescribed herein. In particular, the embodiments described herein relateto improved structures for a backing plate, a caliper bracket, an axleflange, and a parking brake anchor for use in a vehicle drum-in-hat discbrake assembly.

Most vehicles are equipped with a brake system for slowing or stoppingmovement of the vehicle in a controlled manner. A typical brake systemfor an automobile or light truck includes a disc brake assembly for eachof the front wheels and either a drum brake assembly or a disc brakeassembly for each of the rear wheels. In some instances, the disc brakeassembly can be a “drum-in-hat” type of disc brake assembly. The brakeassemblies are actuated by hydraulic pressure or pneumatic pressuregenerated when an operator of the vehicle depresses a brake pedal. Thestructures of these drum brake assemblies and disc brake assemblies, aswell as the actuators therefore, are well known in the art.

A typical drum-in-hat type of disc brake assembly includes ahydraulically or pneumatically actuated disc service brake and amechanically actuated drum-in-hat parking and emergency brake. The discservice brake includes a rotor which is secured to the wheel of thevehicle for rotation therewith. The rotor includes a pair of opposedfriction plates, which are selectively engaged by portions of a caliperassembly. The interior of the rotor defines a cylindrical brakingsurface.

A caliper assembly is slidably supported by pins secured to a mountingflange. The mounting flange is secured to a non-rotatable component ofthe vehicle, such as the steering knuckle or the axle flange. Thecaliper assembly includes a pair of brake shoes which are disposed onopposite sides of the rotor. The brake shoes are operatively connectedto one or more hydraulically actuated pistons for movement between anon-braking position, wherein they are spaced apart from the opposedfriction plates of the rotor, and a braking position, wherein they aremoved into frictional engagement with the opposed friction plates of therotor. When the operator of the vehicle depresses the brake pedal, thepiston urges the brake shoes from the non-braking position to thebraking position so as to frictionally engage the friction plates of therotor and thereby slow or stop the rotation of the associated wheel ofthe vehicle.

The drum-in-hat parking and emergency brake includes a pair of opposedarcuate brake shoes which are supported on a backing plate for selectivemovement relative thereto. The backing plate is secured to the mountingflange, or alternatively, can be formed integral therewith. Each of thebrake shoes has a friction pad or lining secured thereto. The brakeshoes extend within the cylindrical braking surface of the rotor. Toeffect parking and emergency braking action, the operator of the vehiclemanually pulls an actuating lever. The lever is connected to anactuation cable having a park brake cable end which, when pulled,actuates a mechanical actuating mechanism. The actuating mechanism islocated adjacent one of the ends of the brake shoes and is operative tomove the brake shoes outwardly apart from one another such that thefriction pads frictionally engage the cylindrical braking surface of therotor. Such frictional engagement causes slowing or stopping of therotational movement of the rotor and, therefore, the wheel of thevehicle in a controlled manner.

US Patent Application Publication No. 2005/0145451 discloses a vehiclebrake assembly having a drum-in-hat adapter 12. The adapter 12 is arelatively large stamped part having a large opening 20 for receivingthe outer end of an axle.

U.S. Pat. No. 6,729,444 discloses a drum-in-hat disc brake assembly alsohaving a relatively large drum-in-hat adapter 14. The adapter 14 is arelatively large stamped part having a large opening 22 for receivingthe outer end of an axle.

U.S. patent application Ser. No. 12/004,127 discloses an improvedstructure for a parking brake actuator 25 for a vehicle drum-in-hat discbrake assembly.

US Patent Application Publication No. 2007/0227840 discloses drum-in-hatdisc brake assembly wherein a first fastener is provided for securingthe abutment tower to the caliper bracket assembly. A plurality ofsecond fasteners is provided for securing the caliper bracket assemblyand the shield to the axle flange.

SUMMARY

The present application describes various embodiments of a vehicledrum-in-hat disc brake assembly. In one embodiment, the drum-in-hat discbrake assembly has a disc service brake and a drum-in-hat parking andemergency brake, and further includes a backing plate adapted to supporta drum brake shoe assembly of the drum-in-hat parking and emergencybrake. The backing plate has a centrally located opening defining anaxis and at least two smaller mounting apertures formed therein aboutthe centrally located opening thereof. The drum-in-hat disc brakeassembly also includes a parking brake anchor and an axle flange. Theaxle flange has at least two mounting apertures formed therein, and isstructured and configured to be secured to an axle tube which in turn isstructured and configured to extend through the centrally locatedopening of the backing plate. The drum-in-hat disc brake assembly alsoincludes a caliper bracket adapted to support a disc brake caliperassembly of the disc service brake, wherein the caliper bracket has atleast two mounting apertures formed therein. The parking brake anchorincludes a bracket portion having a pair of studs extending axiallyoutwardly therefrom. The studs are structured and configured to extendthrough the respective mounting apertures of the backing plate, the axleflange, and the caliper bracket for securing the caliper bracket,parking brake anchor, and the backing plate to the axle flange.

Other advantages of the vehicle drum-in-hat disc brake assembly willbecome apparent to those skilled in the art from the following detaileddescription, when read in light of the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an outboard side elevational view of a prior art vehicledrum-in-hat disc brake assembly.

FIG. 2 is an exploded perspective view of a first embodiment of thedrum-in-hat disc brake assembly.

FIG. 3 an enlarged perspective view of a portion of the drum-in-hat discbrake assembly illustrated in FIG. 2.

FIG. 4 is an enlarged perspective view of an alternate embodiment of theaxle flange illustrated in FIGS. 2 and 3.

FIG. 5 is an exploded perspective view of a second embodiment of thedrum-in-hat disc brake assembly.

FIG. 6 is a plan view of the parking brake anchor illustrated in FIG. 5.

FIG. 7 is a plan view of an alternate embodiment of the anchorillustrated in FIG. 5.

FIG. 8 is a plan view of an alternate embodiment of the anchorillustrated in FIGS. 2 and 3.

FIG. 9 is a plan view of another alternate embodiment of the anchorillustrated in FIG. 5.

FIG. 10A is a perspective view of a portion of a third embodiment of thedrum-in-hat disc brake assembly.

FIG. 10B is a perspective view of a portion of a forth embodiment of thedrum-in-hat disc brake assembly.

FIG. 11A is a perspective view of a portion of a fifth embodiment of thedrum-in-hat disc brake assembly.

FIG. 11B is a perspective view of a portion of a sixth embodiment of thedrum-in-hat disc brake assembly.

FIG. 12 is a perspective view of a portion of the drum-in-hat disc brakeassemblies illustrated in FIGS. 10B and 11B.

DETAILED DESCRIPTION

A known vehicle drum-in-hat disc assembly is indicated generally at 10in FIG. 1. The actuator includes an adjustable rivet 34 for eliminatingdimensional tolerances in the like assembly 26. FIG. 1 an outboard sideelevational view of a prior art vehicle drum-in-hat disc brake assembly,indicated generally at 10. The vehicle drum-in-hat disc brake assembly10 includes a hydraulically or pneumatically actuated disc service brake(not shown), and a drum-in-hat parking and emergency brake. In theillustrated embodiment, the vehicle drum-in-hat parking and emergencybrake is a sliding shoe type of brake. The general structure andoperation of the vehicle drum-in-hat disc brake assembly is conventionalin the art.

As shown in FIG. 1, the illustrated vehicle drum-in-hat disc brakeassembly 10 includes a drum-in-hat adapter assembly 12, a backing plate14, and a drum-in-hat parking and emergency brake portion, indicatedgenerally at 16. The adapter assembly 12 includes a drum-in-hat adapterportion 2 and an axle flange portion 4 formed integrally therewith. Theadapter assembly 12 is illustrated as being a one-piece casting and isadapted for enclosing a rotatable axle (not shown). To accomplish this,the adapter assembly 12 includes a relatively large opening 20 and aplurality of smaller lug bolt mounting holes 22 formed therein about theopening 20. The opening 20 permits an outer end of an axle to extendtherethrough to the vehicle wheel (not shown), and suitable fasteners(not shown), are disposed in the lug bolt mounting holes 22 to securethe adapter assembly 12 to the associated vehicle component.

The adapter assembly 12 further includes an abutment (not shown)integrally cast with the drum-in-hat adapter assembly 12. Theillustrated backing plate 14 of the drum-in-hat disc brake assembly 10is preferably a stamped metal backing plate and includes a relativelylarge central opening (not shown) and a plurality of smaller openings(not shown) formed therein about the central opening 20 of thedrum-in-hat adapter assembly 12. The central opening permits an outerend of the rotatable axle (not shown) to extend therethrough to a wheel(not shown) of the vehicle. The smaller openings are adapted to receivesuitable fasteners, such as threaded mounting studs (not shown).

Such studs may extend through the openings formed in the backing plate14 and the openings 22 drum-in-hat adapter assembly 12. The threadedends of the studs may be threadably received in threaded openings (notshown) provided in the associate vehicle component to secure the backingplate 14 and the drum-in-hat adapter assembly 12, and therefore thedrum-in-hat disc brake assembly 10, to the associated vehicle component.Alternatively, the backing plate 14 and/or the drum-in-hat adapterassembly 12 can be secured to one another and/or can be secured to theassociated vehicle component by other methods.

The vehicle drum-in-hat disc brake assembly 10 further includes a pairof brake shoes 50 and 50′ supported thereon by conventional pivot pinand spring-clip assemblies, indicated generally at 52. Each of theassemblies 52 includes a pin 54 which extends through an opening (notshown) of the backing plate 14 and through associated opening (notshown) provided in the brake shoes 50 and 50′. The pins 54 have outerends which are adapted to be fastened or secured to clips 56 of thespring-clip assemblies 52 to secure the brake shoes 50 and 50′ to thebacking plate 14 in a conventional manner. The illustrated drum-in-hatbrake assembly 10 also includes a first retraction spring 58 and asecond retraction spring 60. The exemplary retraction springs 58 and 60are illustrated as a pair of retraction springs. It will be understoodhowever, that the only a single retraction spring, such as either thespring 58 or the spring 60 may be provided.

The drum-in-hat parking and emergency brake portion 16 of the brakeassembly 10 includes the pair of brake shoes 50 and 50′ supported on thebacking plate 14. Structurally, the brake shoes 50 and 50′ areessentially mirror images of one another, and like reference numbers areused to indicate similar parts. The brake shoes 50 and 50′ includerespective web portions 62 and 62′ which are generally flat andcrescent-shaped. Generally arcuate-shaped rim portions 64 and 64′ aresecured to the opposed outer curved surfaces of the web portions 62 and62′, such as by welding. A friction pad 66 is secured to the outerarcuate surface of the rim portion 64 of the brake pad 50, while afriction pad 66′ is secured to the outer arcuate surface of the rimportion 64 of the brake pad 50′. The vehicle drum-in-hat parking andemergency brake 10 further includes a manual adjusting mechanism,indicated generally at 70, to compensate for thinning of the frictionpads 66 and 66′ resulting from wear caused by repeated use.

Referring now to FIGS. 2 and 3 a portion of a first embodiment of avehicle drum-in-hat disc assembly is indicated generally at 100. Thevehicle drum-in-hat disc brake assembly 100 includes a hydraulically orpneumatically actuated disc service brake (not shown), and a drum-in-hatparking and emergency brake. In the illustrated embodiment, the vehicledrum-in-hat parking and emergency brake is a sliding shoe type of brake.The general structure and operation of the vehicle drum-in-hat discbrake assembly is conventional in the art. Thus, only those portions ofthe vehicle drum-in-hat disc brake assembly which are necessary for afull understanding of this invention will be explained and illustratedin detail.

Although this invention will be described and illustrated in connectionwith the particular vehicle drum-in-hat disc brake assembly 100disclosed herein, it will be appreciated that this invention may be usedin connection with other sliding shoe types, or pivoted shoe types, ofdrum-in-hat disc brake assemblies in connection with the associatedparking and emergency brake portion if so desired.

As shown in FIGS. 2 and 3, the illustrated vehicle drum-in-hat discbrake assembly 100 includes a drum-in-hat bracket or parking brakeanchor 102, a splash shield or backing plate 104, an axle flange 106, acaliper bracket 108, and a drum brake shoe assembly 110.

The illustrated backing plate 104 of the drum-in-hat disc brake assembly100 is a stamped metal backing plate and includes a relatively largecentral opening 112 and a plurality of smaller mounting apertures 114and 115 formed therein about the central opening 112. The centralopening 112 permits an axle tube 116, described herein below, to extendtherethrough. The smaller mounting apertures 115 are adapted to receivesuitable fasteners, such as threaded mounting studs 118 or otherthreaded fasteners 120.

In the illustrated embodiment, a generally elongated slotted opening 122is structured and configured to allow a lever arm 124 of a parking brakeand emergency brake actuator (not shown) to extend therethrough.

The illustrated backing plate 104 includes a tab 128 extending axiallyoutwardly adjacent the centrally located opening 112. The tab 128 may beformed during the stamping process. The tab 128 has an aperture 130formed therein and is structured and configured for receiving a threadedfastener 132 for securing the backing plate 104 to the axle tube 116.

Advantageously, the tab 128 provides an economical and relatively simpleadditional attachment point, i.e., in addition to the mounting apertures150 and 152 of the axle flange 106 (described in detail below).

The illustrated parking brake anchor 102 is a one-piece casting formedfrom iron. It will be understood that the brake anchor 102 may be formedfrom any other desired metal and non-metal. The brake anchor 102includes a bracket portion or anchor body 134 and an abutment 136. Theillustrated abutment 136 is integrally cast with the anchor body 134.The brake anchor 102 further includes a generally elongated slottedopening 138. The slotted opening 138 is structured and configured toallow the lever arm 124 of the parking brake and emergency brakeactuator 126 to extend therethrough. A pair of threaded mounting studs118 extend axially outwardly of the bracket portion 134. The studs 118are structured and configured to extend through the respective apertures115, 150, and 166 and 168 of the backing plate 104, the axle flange 106,and the caliper bracket 108, respectively, for securing the caliperbracket 108, parking brake anchor 102, and the backing plate 104 to theaxle flange 106. In the illustrated embodiment, the studs 118 arethreaded for receiving internally threaded nuts 119.

A first alternate embodiment of the parking brake anchor is showngenerally at 140 in FIG. 8. In the embodiment illustrated in FIG. 8, theparking brake anchor 140 includes a slightly enlarged anchor body 142relative to the anchor body 134 and includes the slotted opening 138 andthe threaded mounting studs 118. Additionally, two mounting apertures146 are formed outboard of the studs 118, structured and configured toreceive other suitable fasteners, such as the threaded fasteners 120, asshown in FIG. 2.

The illustrated axle flange 106 may be a metal forging or stamping andincludes a flange portion 107 having a substantially arcuate edge 146(lower edge when viewing FIG. 2) structured and configured to be securedto an outer surface of the axle tube 116. The illustrated axle flange106 is welded to the axle tube 116. The flange portion 107 furtherincludes generally elongated slotted opening 148 structured andconfigured to allow the lever arm 124 of the parking brake and emergencybrake actuator (not shown) to extend therethrough. A plurality ofsmaller mounting apertures 150 and 152 are formed therein outboard ofthe slotted opening 122. The smaller mounting apertures 150 arestructured and configured to receive the threaded mounting studs 118.The mounting apertures 152 are structured and configured to receiveother suitable fasteners, such as the threaded fasteners 120.

The illustrated caliper bracket 108 is structured and configured tosupport a disc brake caliper assembly of the disc service brake and hasat least two mounting apertures formed therein. The caliper bracket 108illustrated in FIG. 2 includes a pair of axially and outwardly extendingarms 154 and 156 which are interconnected at their inboard ends by aninner tie bar 158 and at their outboard ends by an outer tie bar 160.The caliper bracket 108 further includes a pair of mounting legs orextensions 162 and 164. In the illustrated embodiment, the legs 162 and164 extend from the inner tie bar 158.

The mounting leg 162 includes an aperture 162A formed therethrough and aslot 166. The mounting leg 164 includes an aperture 164A formedtherethrough and a slot 168. In the illustrated embodiment, theapertures 162A and 164A are non-threaded apertures. Alternatively, thestructure of the caliper bracket 108 including the apertures 162A and164A can be other than illustrated if so desired. The slots 166 and 168are structured and configured to receive the parking brake anchor studs118.

The studs 118 may extend through the mounting apertures 114 formed inthe backing plate 104, the mounting apertures 150 formed in the axleflange 106, and the slots 166 and 168 of the caliper bracket 108. Thestuds 118 may secured by threaded nuts (not shown), to secure thebacking plate 104, the parking brake anchor 102, the caliper bracket 108and the axle flange 106, and therefore the drum-in-hat disc brakeassembly 100, to the associated vehicle component.

Referring now to FIG. 5, the caliper bracket 108 may be formed with theapertures 162A and 164A and a second pair of apertures 167 and 169 inlieu of the slots 166 and 168. Alternatively, the caliper bracket 108may be formed with only one pair of apertures; either the apertures 162Aand 164A or the apertures 167 and 169. The one pair of apertures may bethreaded, or if desired, formed without threads.

Referring now to FIG. 4, an alternate embodiment of the axle flange isshown generally at 170. The axle flange 170 is formed from twocomponents, and includes a flange portion 172 and a substantiallyU-shaped collar portion 174. In the illustrated embodiment, the collarportion 174 is welded to the flange portion 172. An outer edge surface176 (lower edge when viewing FIG. 4) of the flange portion 172 and aninner edge surface 178 of the collar portion 174 cooperate to define anopening 180 structured and configured to be secured, such as by welding,to an outer surface of an axle tube 116 extending therethrough. Thecollar portion 174 includes an aperture 182 formed therein. The aperture182 is structured and configured for receiving a threaded fastener 184for securing the axle flange 106 to the backing plate 104.Alternatively, the flange portion 172 and the collar portion 174 neednot be welded to one another. For example, if desired the flange portion172 and the collar portion 174 may be simultaneous welded to the axletube 116 in a single manufacturing step.

The flange portion 172 further includes a generally elongated slottedopening 186. The slotted opening 186 is structured and configured toallow the lever arm 124 of the parking brake and emergency brakeactuator 126 to extend therethrough. The flange portion 172 alsoincludes a plurality of smaller mounting apertures 188 formed thereinoutboard of the slotted opening 186.

Advantageously, the two-piece axle flange 106 significantly reduceswaste associated with prior art axle flanges, such as the axle flange 16disclosed in U.S. Pat. No. 6,729,444, wherein the opening 72 is formedby stamping and discarding the material removed.

A further advantage is that the axle flange 106 provides 360 degreesupport of the axle tube 116 and the axle tube 116 may be welded to theaxle flange 106 about the entire 360 degrees of its circumference when astronger connection between the axle tube 116 and the axle flange 106,such as in large trucks or other large vehicles, is desirable.

Referring now to FIGS. 5 and 6, a second alternate embodiment of theparking brake anchor is shown generally at 190. The parking brake anchor190 includes an anchor body 192 and an abutment 194. The brake anchor190 further includes the generally elongated slotted opening 138 for thelever arm 124 of the parking brake and emergency brake actuator 126. Apair of stud collars 196 extend axially outwardly of the anchor body192. The illustrated stud collars 196 have internal threads and arestructured and configured to receive threaded fasteners 197 for securingthe caliper bracket 108, parking brake anchor 190, and the backing plate104 to the axle flange 106. The stud collars 196 are further structuredand configured to extend through the apertures 115 of the backing plate104. The stud collars 196 are further structured and configured toextend through at least a portion of the apertures 150 of the axleflange 106. In the illustrated embodiment, the stud collars 196 do notextend completely through the apertures 150 of the axle flange 106.

Referring to FIG. 7, a third alternate embodiment of the parking brakeanchor is shown generally at 198. The parking brake anchor 198 issubstantially identical to the parking brake anchor 190, but includestwo mounting apertures 200 formed outboard of the stud collars 196. Themounting apertures 200 are structured and configured to receive othersuitable fasteners, such as the threaded fasteners, such as thefasteners 197 shown in FIG. 5. In the illustrated embodiment, the studcollars 196 are shown as having internal threads. It will be understoodhowever, that such internal threads are not required. For example, studcollars 196 may be provided without threads and be used to allow anytype of fastener to pass therethrough, and/or to locate the anchor 198relative to the backing plate 104 and the axle flange 106.

In the embodiments described above, slotted openings, for example theslotted openings 138, 122, 148 in the parking brake anchor 102, thebacking plate 104, and the axle flange 106, respectively, are structuredand configured to allow the lever arm 124 of the parking brake andemergency brake actuator 126 to extend therethrough. It will beunderstood that such slotted openings are not required. For example, inembodiments of the drum-in-hat disc brake assembly (not shown) having a“blade lever” type actuator (not shown) rather than the center-pull typeactuator having the lever arm 124, the slotted openings 138, 122, 148are not required (see FIG. 5).

Referring to FIG. 9, a fourth alternate embodiment of the parking brakeanchor is shown generally at 202. The parking brake anchor 202 issimilar to the parking brake anchor 198, but includes only one studcollar 196 centrally located on the anchor 202. In the illustratedembodiment, the stud collar 196 is centered on the symmetricalcenterline of the anchor 202. In the illustrated embodiment, the studcollar 196 is shown as having internal threads. It will be understoodhowever, that such internal threads are not required. For example, thestud collar 196 may be provided without threads and be used to allow anytype of fastener to pass therethrough, and/or to locate the anchor 202relative to the backing plate 104 and the axle flange 106.

Referring now to FIGS. 10A and 10B, a portion of a third and fourthembodiment of a vehicle drum-in-hat disc assembly is indicated generallyat 210 and 210′, respectively. The vehicle drum-in-hat disc brakeassembly 210, 210′ is similar to the drum-in-hat disc brake assembly 100and includes a hydraulically or pneumatically actuated disc servicebrake (not shown), and a drum-in-hat parking and emergency brake, suchas illustrated in FIGS. 2 and 3.

The illustrated vehicle drum-in-hat disc brake assembly 210, 210′includes a drum-in-hat bracket or parking brake tower or anchor 212(best shown in FIG. 12), a splash shield or backing plate 214, an axleflange 216, a caliper bracket 218, and a drum brake shoe assembly (notshown).

The illustrated backing plate 214 of the drum-in-hat disc brake assembly210, 210′ is a stamped metal backing plate and is substantiallyidentical to the backing plate 104. As best shown in FIG. 12, thebacking plate 214 includes a relatively large central opening 220 and aplurality of smaller mounting apertures 222 formed therein about thecentral opening 220. The central opening 220 permits an axle tube (notshown) to extend therethrough. The smaller mounting apertures 222 areadapted to receive suitable fasteners, such as threaded fasteners 224 orother desired fasteners.

The illustrated parking brake anchor 212 is a one-piece casting formedfrom iron. It will be understood that the brake anchor 212 may be formedfrom any other desired metal and non-metal. The brake anchor 212includes an anchor body 226 and an abutment 228. In the illustratedembodiment, legs 227 extend outwardly of the body 226. A pair ofmounting apertures 229 are formed in each leg 227 and are structured andconfigured to receive the threaded fasteners 224 for attaching the axleflange 216 to the backing plate 214 and the anchor 212.

The brake anchor 212 further includes a collar portion 230 having anopening 232 therethrough. The opening 232 is structured and configuredto allow the lever arm 234, 234′ of a parking brake and emergency brakeactuator to extend therethrough. A pair of mounting apertures 236 areformed in the collar portion 230 about the opening 232.

The collar portion 230 of the anchor 212 extends through an opening inthe backing plate 214 and is structured and configured for mounting anelectronic actuator 238 thererto. The mounting apertures 236 arestructured and configured to receive fasteners, such as threadedfasteners (not shown) for attaching the actuator 238 to the collarportion 230. It will be understood that the electronic actuator 238 beany other desired actuator.

The illustrated axle flange 216 may be a metal forging or stamping andincludes a flange portion 240. As shown in FIGS. 10A and 10B, the flangeportion 240 includes a substantially cylindrical collar portion 241extending outwardly of the flange portion 240 and defining an opening242 structured and configured to be secured to an outer surface of anaxle tube (not shown), such as by welding. In the illustratedembodiment, legs 244 extend outwardly of the flange portion 240 anddefine a peripheral edge or substantially U-shaped opening 246. A pairof mounting apertures 248 is formed in each leg 244 and are structuredand configured to receive the threaded fasteners 224 for attaching theaxle flange 216 to the backing plate 214 and the anchor 212, as bestshown in FIG. 12. Two relatively smaller apertures 250 are also formedin the flange portion 240. The smaller apertures 250 are structured andconfigured to receive threaded fasteners (not shown) or alignment studs(not shown) for positioning the axle flange 216 relative to the backingplate 214. The apertures 250 may receive other suitable fasteners, suchas for example, non-threaded fasteners (not shown).

The caliper bracket 218 illustrated in FIGS. 10A and 10B is structuredand configured to support a twin pod caliper assembly 252. Theillustrated caliper bracket 218 is similar to the caliper bracket 108illustrated in FIG. 2 and includes a pair of mounting legs or extensions253. A pair of apertures 254 are formed in the extensions 253. Theapertures 254 may be threaded or unthreaded and are structured andconfigured to receive the threaded fasteners 224 for attaching thecaliper bracket 218 and the axle flange 216 to the backing plate 214.

The extensions 253 define a peripheral edge or substantially U-shapedopening 256. When assembled, the U-shaped opening 246 of the axle flange216 and the U-shaped opening 256 of the caliper bracket 218 cooperate todefine an enlarged opening or mounting area 258, which exposes thecollar portion 230 and a portion of the surface of the backing plate 214surrounding the collar portion 230. The exposed portion of the surfaceof the backing plate 214 surrounding the collar portion 230 issufficiently large enough to receive and support the electronic actuator238.

It will be understood however, that the electronic actuator 238 is notrequired, and the drum-in-hat disc brake assembly 210′ may be providedwith the lever arm 234, 234′ for connection to an actuation cable (notshown).

Referring now to FIGS. 11A and 11B, and using like reference numbers toindicate corresponding parts, there is indicated generally at 310 and310′ a portion of a fifth and sixth embodiment, respectively, of avehicle drum-in-hat disc assembly. The vehicle drum-in-hat disc brakeassembly 310 310′ is substantially identical to the drum-in-hat discbrake assembly 210, 210′, except that the brake assembly 310, 310′includes an alternate embodiment of a caliper 312, a caliper bracket314, and an actuator 316.

The illustrated vehicle drum-in-hat disc brake assembly 310, 310′includes the drum-in-hat bracket or parking brake tower or anchor 212(best shown in FIG. 12), the backing plate 214, the axle flange 216, anda drum brake shoe assembly (not shown).

The collar portion 230 of the anchor 212 extends through the backingplate 214 and is structured and configured for mounting an electronicactuator 316 thererto. It will be understood that the electronicactuator 238 be any other desired actuator.

The caliper bracket 314 illustrated in FIGS. 11A and 11B is structuredand configured to support a single pod caliper assembly 312. Theillustrated caliper bracket 314 is similar to the caliper bracket 218illustrated in FIGS. 10A and 10B and includes a pair of mounting legs orextensions 318. A pair of apertures 320 are formed in the extensions318. The apertures 320 may be threaded or unthreaded and are structuredand configured to receive the threaded fasteners 224 for attaching thecaliper bracket 314 and the axle flange 216 to the backing plate 214.

The extensions 318 define a peripheral edge or substantially U-shapedopening 322. When assembled, the U-shaped opening 246 of the axle flange216 and the U-shaped opening 322 of the caliper bracket 314 cooperate todefine an enlarged opening 324, which exposes the collar portion 230 anda portion of the surface of the backing plate 214 surrounding the collarportion 230. The exposed portion of the surface of the backing plate 214surrounding the collar portion 230 is sufficiently large enough toreceive and support the electronic actuator 316.

It will be understood however, that the electronic actuator 316 is notrequired, and the drum-in-hat disc brake assembly 310′ may be providedwith the lever arm 234, 234′ for connection to an actuation cable (notshown).

The principle and mode of operation of the drum-in-hat disc brakeassembly have been described in its various embodiments. However, itshould be noted that the drum-in-hat disc brake assembly describedherein may be practiced otherwise than as specifically illustrated anddescribed without departing from its scope.

1. A drum-in-hat disc brake assembly having a disc service brake and adrum-in-hat parking and emergency brake, the drum-in-hat disc brakeassembly comprising: a backing plate adapted to support a drum brakeshoe assembly of the drum-in-hat parking and emergency brake, thebacking plate having a centrally located opening defining an axis, atleast two smaller mounting apertures formed therein about the centrallylocated opening thereof, and a slotted opening; a parking brake anchorhaving a body and an abutment extending outward of the body and furtherincluding a collar portion integrally formed with and extending outwardof the body opposite the abutment and having an opening formed therein,wherein the collar portion extends through the slotted opening in thebacking plate, and wherein a lever arm of a parking and emergency brakeactuator extends through the opening in the collar portion; wherein thecollar portion is configured to have an actuator mounted thereto; anaxle flange having at least two mounting apertures formed therein, theaxle flange structured and configured to be secured to an axle tubewhich in turn is structured and configured to extend through thecentrally located opening of the backing plate; and a caliper bracketadapted to support a disc brake caliper assembly of the disc servicebrake, the caliper bracket having at least two mounting apertures formedtherein; wherein the axle flange includes a flange portion and asubstantially cylindrical portion extending outwardly of the flangeportion, an inner edge surface of the cylindrical portion defining anopening structured and configured to be secured to an outer surface ofthe axle tube extending therethrough.
 2. The drum-in-hat disc brakeassembly according to claim 1, wherein the axle flange includes anaperture formed therein, the aperture structured and configured forreceiving a threaded fastener, the threaded fastener securing the axleflange to the backing plate.
 3. A drum-in-hat disc brake assembly havinga disc service brake and a drum-in-hat parking and emergency brake, thedrum-in-hat disc brake assembly comprising: a backing plate adapted tosupport a drum brake shoe assembly of the drum-in-hat parking andemergency brake; a caliper bracket adapted to support a disc brakecaliper assembly of the disc service brake and mounted to the backingplate, the caliper bracket having a peripheral edge defining asubstantially U-shaped opening; an axle flange mounted to the backingplate and having a peripheral edge defining a substantially U-shapedopening; and a parking brake anchor having a body and an abutmentextending outward of the body; wherein the parking brake anchor furtherincludes a collar portion integrally formed with and extending outwardof the body opposite the abutment and having an opening formed thereinand wherein a lever arm of a parking and emergency brake actuatorextends through the opening in the collar portion; wherein the collarportion is configured to have an actuator mounted thereto; wherein thecollar portion extends through an opening in the backing plate; andwherein the substantially U-shaped opening of the caliper bracket isspaced apart from the axle tube opening formed in the axle flange andspaced apart from the substantially U-shaped opening of the axle flangesuch that an area between the substantially U-shaped opening of the axleflange and the substantially U-shaped opening of the caliper bracketdefines a mounting area exposing the collar portion and a portion of asurface of the backing plate surrounding the collar portion.
 4. Thedrum-in-hat disc brake assembly according to claim 3, further includingan electronic actuator mounted to the collar portion and operativelyconnected to the lever arm